Envelope-enclosed, extended-life electrical contact means having longitudinal deflection-minimizing constraint means therefor



Aug. 29, 3967 M. N. GOVER 3,339,049 ENVELOPE-ENCLOSED, EXTENDED-LIFE ELECTRICAL CONTACT MEANS HAVING LONGITUDINAL DEFLECTION-MINIMIZING CONSTRAINT MEANS THEREFOR Filed June 13, 1966 United States Patent ENVELOPE-ENCLOSED, EXTENDED-LIFE ELEC- TRICAL CONTACT MEANS HAVING LONGI- TUDINAL DEFLECTION-MINIMIZING CON- STRAINT MEANS THEREFOR Marcius N. Gover, Marietta, Ga. (193 N. Murphy Ave., Sunnyvale, Calif. 94086) Filed June 13, 1966, Ser. No. 557,250 17 Claims. (Cl. 200-166) The present invention is a continuation-in-part of my co-pending patent application, Ser. No. 446,807, filed Apr. 9, 1965, now Patent No. 3,284,586.

Generally speaking, the present invention pertains to extended-life electrical contact means or to an arrangement for protecting electrical contacts in a manner such as to greatly prolong the life thereof. This is true in a broad general sense with respect to electrical contact means of any of a great variety of different types. However, one particular application and form for such extended-life electrical contact means which is particularly advantageous will be used throughout this application for purposes of illustration, but should be clearly understood to be non-specifically limiting to such a particular application and form thereof.

The exemplary application and form of such extendedlife electrical contact means referred to in the preceding paragraph is in the distributor of the electrical ignition system of an internal combustion engine where two electrical contact means are employed and are conventionally called distributor points and have been a constant source of trouble because of their extremely repetitive usagethat is, the fact that they must open and close rapidly as long as the internal combustion engine is running, and, thus, said distributor points or contacts tend to become heated during use, resulting in rapid oxidation of the contact surfaces and, in many cases, resulting in transfer of contact material (usually metal) from one contact surface to the other contact surface, which effectively causes pitting of one of the distributor points or contacts and a buildup of material on the other one.

Also, the above-mentioned oxidized distributor points or contact surfaces are much more resistant to the flow of electrical current, and, hence, the contacts become less efiicient and interfere with satisfactory operation of the internal combustion engine, since an inadequate spark will then be available at the spark plugs thereof for proper firing of the air-gas mixture in the combustion chambers of the cylinders of said internal combustion engine. Indeed, ultimately, such reduction in efiiciency of the distributor points may result in a misfiring, or failure to fire, in one or more of the cylinders of the internal combustion engine which not only leads to greatly increased loss of power but ultimately to damage to the engine because of stresses and strains produced by such failure to fire.

Additionally, it should be noted that conventional distributor points are open to atmosphere and exposed to various types of foreign material and contaminants, such as oil and grease, which tend to collect on the distributor points and also tend to produce an increased electrical resistance across the distributor points to the point of ultimate failure thereof.

For these and other reasons, conventional distributor points tend to wear out very rapidly and must be replaced frequently, and it will be noted that the novel extendedlife electrical contact means of the present invention, when incorporated in a distributor for an internal combustion engine, virtually completely overcomes and eliminates the above-mentioned prior art problems since no oxidation of the contact surfaces or distributor points will occur and also since no foreign matter or contaminants will be deposited on the distributor points or contacts. Furthermore, because of the inherent advantages of the extended-life electrical contact means of the present invention, it may be possible to minimize the space, which exists between the distributor points or contacts when separated during the operation thereof by the rotary cam of the conventional distributor and to consequently shorten the distance from the contacts to the effective pivot point around which one of said contacts pivots, thus reducing the length and mass of the moving portion of the complete device. This is primarily made possible by reason of the inert gaseous atmosphere provided therebetween in the novel arrangement of the present invention, which, additionally, will tend to minimize any possibility of electrical arcing between the contact members occurring when they are separated, and this, of course, will reduce heating of the contact surfaces and any burning away and/or transfer of contact material to an absolute minimum.

All of the above-mentioned factors tend to greatly extend and lengthen the life of the distributor points, or electrical contact means, so that it will be unnecessary to replace same frequently in the undesirable manner of conventional prior art distributor points. It should also be noted that the inert gaseous atmosphere surrounding the contacts may make a reduction in contact pressure possible, which, in turn, may eliminate the necessity for an auxiliary return biasing spring means.

With the above points in mind, it is an object of the present invention to provide novel extended-life electrical contact means which may comprise two electrical contact members, or any desired number thereof, effectively surrounded and enclosed by an envelope means relatively movably resiliently carrying at least one of said contact members for relative forcible displacement with respect to at least one other of said contact members positioned therein in order to bring about effective electrical engagement and electrical disengagement thereof, and with said contact members all being within said resilient envelope means and being surrounded by a nonoxidizing, substantially inert gaseous atmosphere.

Experimentation has shown that when a distributor cam is rotated at high speed by an internal combustion engine, and correspondingly laterally displaces the abovementioned envelope means (which is accomplished by cam follower means coupled to the envelope means and displaced by said rotating distributor cam), some degree of longitudinal displacement of the envelope means may also occur, either in an extension direction or a compression direction depending upon the direction of rotation of the engine-operated cam. This is undesirable since it leads to misalignment of one of the two electrical contact members, which is carried by the inside of said envelope means and since it also leads to early fatigue of the thinwalled material of which the envelope means is made and to the likelihood of an early structural failure or rupture thereof. This, of course, would allow the inner gaseous atmosphere to be contaminated and dissipated and would eliminate most of the advantages of the present invention.

Therefore, it is highly desirable to substantially eliminate any such tendency toward longitudinal displacement of the envelope means in response to high-speed rotation of the engine-driven cam and, for this purpose, the present invention includes longitudinal deflection-minimizing constraint means which is effectively longitudinally coupled between a rigid mounting bracket (which also carries the rear end of the envelope means) and an outwardly or forwardly spaced portion of said envelope means which is effectively provided with the above-mentioned cam follower means.

The effective shunt or bridging connection of longitudinally spaced portions of the envelope means between the effective connection of the cam follower means thereto and the rigid cantilever mounted rear end of the envelope means acts in a manner such as to substantially prevent any longitudinal deflection of the portion of the envelope means therebetween, while freely allowing lateral cantilever deflection of the envelope means by the cam follower means in response to operation thereof by the engine-driven cam. This is made possible by reason of the fact that said constraint means is relatively stiff and has little compliance in a longitudinal direction, but has great compliance and very little stiffness in a lateral direction, thus allowing the desired lateral cantilever deflection of the envelope means in a manner necessary for the operation of the apparatus of the present invention, while substantially preventing any elongation or shortening of the envelope means as a result of high-speed rotation of the engine-driven cam. This avoids the previously-mentioned problems of possible misalignment of the electrical contacts and/ or fatigue and possible structural failure or rupture of the envelope means, which is likely to occur when the engine-driven cam is rotated at high speed and no longitudinal constraint means is provided.

Therefore, it is a further object of the present invention to provide apparatus of the character referred to in the preceding object which also includes such longitudinal deflection-minimizing constraint means coupled to the envelope in the manner referred to hereinabove for the purposes briefly outlined hereinabove.

It is a further object of the present invention to provide apparatus of the character referred to in the preceding object, wherein the effective coupling of the longitudinal deflection-minimizing constraint means between said rigid envelope-mounting bracket and the cam-follower-mounting portion of said envelope means is provided by direct rigid connection of a rear end of said longitudinal constraint means to said rigid mounting bracket and by effective connection of an outward or front end of said constraint means to said cam follower means, which, in turn, is effectively coupled with respect to the adjacent portion of said envelope means.

It is a further object of the present invention to pro- ,vide apparatus of the character referred to in the preceding object, wherein said longitudinal deflection-minimizing constraint means comprising an effective biasing spring means which normally forcibly resiliently laterally biases said forwardly spaced portion of said envelope means in a first manner such as to cause a pair of electrical contact members therewithin to normally be in electricallyengaged relationship or in a second manner such as to cause a pair of such electrical contact members positioned therewithin to normally be in electrically-disengaged relationship with respect to each other-in either case being adapted to be operated into the opposite condition as a result of rotation of an engine-mounted cam in a manner causing forcible lateral deflection of said envelope means against the action of said biasing spring means.

It is a further object of the present invention to provide extended-life electrical contact means of the character referred to above, which is in a form effectively comprising distributor points or contact means carried by mounting elements and structure substantially functionally equivalent to the corresponding portions of a conventional distributor, and distributor points carried thereby, of an internal combustion engine and suitable for exact mounting replacement of such conventional portions of a conventional internal combustion engine distributor.

It is a further object of the present invention to provide extended-life electrical contact means having any or all of the features and advantages referred to herein, either generically or specifically, and/ or individually or in combination, and which is of a relatively simple inexpensive, easy-to-mount, and easy-to-install construction such as to be conducive to widespread use thereof.

Further objects are implicit in the detailed description which follows hereinafter (which is to be construed as exemplary of the present invention, but which is not to be considered as specifically limiting it to the exemplary forms described hereinafter), and said objects will be apparent to persons skilled in the art after a careful study of the detailed description which follows hereinafter.

For the purpose of clarifying the nature of the present invention, several exemplary embodiments thereof, taking the form of distributor point assemblies suitable for mounting on a conventional internal combustion engine distributor, are illustrated in the hereinbelow-described figures of the accompanying single drawing sheet and are described in detail hereinafter.

FIG. 1 is a top view, partly in elevation and partly in section, illustrating one exemplary embodiment of the improved form of the present invention wherein it comprises a replacement distributor points assembly embodying the novel long-life electrical contact means of the present invention and adapted to comprise a complete replacement for a conventional prior art distributor points assembly of a conventional prior art internal combustion engine distributor, which is shown in top plan view with the cover removed in FIG. 1. In this view, the enclosing envelope means (with the exception of the center portion thereof) and the means mounting same at the rear end are shown in section substantially on a central longitudinal plane in order to clearly show the interior positioning of the opposed electrical contact means or points when the apparatus and the conventional driving cam of the distributor are in the non-deflection positional relationships shown in FIG. 1.

FIG. 2 is a fragmentary view, generally similar to FIG. 1, but shows the distributor points assembly in the positionally deflected relationship produced by rotation of the conventional distributor cam from the position shown in FIG. 1 into the position shown in FIG. 2, which results in effectively opening or separating the distributor points, or electrical contact means, temporarily.

FIG. 3 is an enlarged fragmentary view taken substantially along the plane indicated by the arrows 3-3 of FIG. 1.

FIG. 4 is an enlarged fragmentary view of a slight modification of the invention, partly comprising a plan view and partly comprising a sectional view taken substantially on a central plane of the outer or remote end portion of the enclosing envelope means of FIG. 1 and of the cam follower means and a cooperating portion of an engine-driven distributor cam. In other words, this comprises an enlargement of a modification of the corresponding portion of the structure shown in FIG. 1.

FIG. 5 is a fragmentary view taken substantially along the plane indicated by the arrows 55 of FIG. 4.

FIG. 6 is a view very similar to FIG. 4, but illustrates a further modification of the invention.

FIG. 7 is a cross-sectional view taken substantially along the plane indicated by the arrows 77 of FIG. 6.

FIG. 8 is a view very similar to FIG. 4, but illustrates a further very slight modification of the FIG. 4 form of the invention.

FIG. 9 is a cross-sectional view taken substantially long he plane indicated by arrows 99 of FIG. 8.

FIG. 10 is a view very similar to FIG. 6, but illustrates a further very slight modification of the FIG. 6 form of the invention.

FIG. 11 is a cross-sectional view taken substantially along the plane indicated by the arrows 1111 of FIG. 10.

FIG. 12 is a fragmentary, greatly-reduced-size view similar to corresponding portions of the FIG. 1 form of the invention, but illustrating a modified arrangement of the two electrical contact means (open), when the flat of the distributor cam is adjacent to the cam follower means, differing from the closed contact arrangement shown in FIG. 1 when the distributor cam is in the same relationship to the cam follower means thereof.

It should be noted that in the cross-sectional views comprising FIGS. 3, 5, 7, 9, and 11, all portions of the apparatus positioned below the level of the structure shown in the view and lying behind the remote end of the envelope means are deleted from each of said views for reasons of drawing simplicity and clarity.

Generally speaking, the extended-life electrical contact means of the present invention may be said to comprise a hollow enclosing envelope means provided therein with a first contact member movable therewith and a second fixed contact member non-movable therewith, and adapted to be controllably engaged and/ or disengaged with respect to said first contact member when said enclosing envelope means is forcibly elastically deflected and then released from said forcible elastic deflection to allow it to return to a normal at-rest position.

The invention is intended to include and comprehend both a normally open contact arrangement, wherein the forcible elastic deflection of the envelope means produces electrical engagement of the first and second electrical contact members and wherein the release thereof causes disengagement of said first and second electrical contact members; and to also include the opposite arrangement wherein the forcible elastic deflection of said enclosing envelope means produces disengagement of said first and second electrical contact members and wherein the release thereof produces engagement of said first and second electrical contact members.

In other words, the present invention, in a broad sense, may be said to comprise both a normally open extendedlife electrical contact means arrangement and a normallyclosed extended-life electrical contact means arrangement. However, since the exemplary form of the invention chosen to illustrate the broad principles thereof comprises a replacement distributor point assembly, and since such distributor point assemblies are conventionally normally closed, the arrangement illustrated in FIGS. 1-11 comprises a normally-closed, extended-life electrical contact means. However, it should be clearly understood that this exemplary form is illustrative only, and FIG. 12 is intended to fully disclose and include and comprehend such a normally-open extended-life electrical contact means also.

In the exemplary first form illustrated, the invention includes a hollow longitudinal cantilever-type enclosing envelope means, generally designated at 20, which is made of electrically conductive metallic material and which is provided at the rear end 22 thereof with rigid electrically conductive metallic mounting bracket means, generally designated by the reference numeral 24, which has a base portion 26 fastened at opposite ends by a pair of fastening screw means 28 extending through corresponding position-adjusting slot means 30 to the inside top surface portion 32 of the conventional internal combustion engine distributor, generally indicated at 34.

Said mounting bracket means 24 also includes an upstanding clamping portion indicated at 36, which may comprise a pair of laterally spaced fingers or a complete enclosing ring, rigidly clamping the rear end 22 of the 6 hollow horizontal cantilever-type enclosing envelope means 20 in said clamping members 36 and in a rigid fixed relationship with respect to the remainder of the mounting bracket means 24 and the complete distributor 34.

However, it should be noted that the front end 38 of the hollow longitudinal cantilever-type enclosing envelope means 20 is not fixed to anything but is freely supported in spaced relationship above the inside top surface portion 32 of the conventional distributor 34 and is also spaced above the flat bottom portion 26 of the mounting bracket means 24 in what might be termed a cantilever fashion.

In the exemplary form illustrated, the front end 38 of the enclosing envelope means 20 is effectively sealed by having a sealing closure cap 40 positioned over the initially open end 42 of the tube forming said longitudinal enclosing envelope means 20. It will be understood that the initially open end 42 of the longitudinal enclosing envelope means 20 may facilitate interior adjustment of the electrical contact members which will be referred to hereinafter, after which said sealing closure cap 40 may be placed over the open end 42 and sealed into place in any suitable manner, such as by soldering, brazing, welding, or adhesively, cohesively, or mechanically fastening same in place.

The exemplary first form of the invention is also provided with a rigid longitudinal support member 44 of electrically conductive metallic material extending through the rear end 22 of the longitudinal enclosing envelope means 20 to a position exterior thereof and there having an upwardly bent rear end, as indicated at 46, which is effectively provided with electrical connector means, such as generally designated at 48, and which is shown as comprising a pair of vertically adjacent threaded nuts mounted on a corresponding exteriorly threaded portion of said rear end part 46 of said rigid longitudinal sup port member 44.

The forward end of said rigid longitudinal support member 44 extends forwardly along and within the interior chamber 50 defined within the enclosing envelope means 20 to a position spaced from the forward end closure cap 40 thereof and also spaced from any of the side wall portions 20' of the enclosing envelope means 20, and it should be noted that the portion of said rigid longitudinal support member 44 which passes through the rear end 22 of said enclosing envelope means 20, also passes substantially centrally through the clamping means 36 and is firmly mounted in said position and in electrically insulated relationship with respect to the enclosing envelope means 20 by an inner sealing plug means 52 of electrical insulating material which is firmly fastened within the otherwise open rear end 22 of the longitudinal enclosing envelope means 20 and to which said rear end 22 of said enclosing envelope means 20 is firmly sealed by any suitable means, such as pressure, or various sealing compounds or the like. Also, in the event that the clamping means 36 comprises a complete enclosing ring, this may provide an effective seal between the rear end 22 of the enclosing envelope means 20 and said sealing and insulating plug means 52.

In the first exemplary form illustrated, a first electrical contact member 54 is eflectively carried by an inside sur face part of a side wall portion 20 of said enclosing envelope means 20 and is in electrical engagement therewith and, thus, by way of the clamping portion 36 and the bottom portion 26 of the mounting bracket means 24, may be said to be grounded to the electrically conductive top inside surface wall 32 of the distributor 34, since said distributor 34 is conventionally grounded to an internal combustion engine mounting same.

In the exemplary form illustrated, a second electrical contact member 56 is carried by a forward end of said rigid longitudinal support member 44 aligned with, 0pposed to, and facing said first electrical contact member 54, and normally in electrical engagement therewith except when forcibly disengaged therefrom by operation of the conventional rotary distributor cam 58 from the position shown in FIG. 1 into the position shown in FIG. 2. It will be understood that the contact member 56 is electrically insulated and isolated from the rest of the complete assembly and connects only through the rigid longitudinal support member 44 to the rear end 46 thereof and the electrical connection means 48 which is adapted to be connected to the hot wire or lead of a conventional internal combustion engine ignition system.

The apparatus is provided with longitudinal deflectionminimizing constraint means, one exemplary form of which is generally designated at 60, which is effectively longitudinally coupled between the rigid mounting bracket means 24 and a cam-follower-mounting portion 62 of said envelope means 20 for substantially preventing longitudinal deflection of said envelope means 20 therebetween. Said longitudinal constraint means 60 is adapted to have a very low longitudinal compliance and a very high longitudinal stiffness and a very low lateral stiffness and a high lateral compliance sufficient to allow cantilever lateral deflection of the envelope means 20 in response to rotation of the cam means 58, and corresponding lateral deflection of the cam follower means generally designated at 64. In other words, the longitudinal constraint means 60 allows the free lateral deflection of the envelope means 20 in response to rotation of the distributor cam 58 but minimizes or virtually prevents either any longitudinal effective extension of the envelope means 20 or any effective longitudinal shortening of the envelope means 20 in response to counter-clockwise rotation or clockwise rotation, respectively, of the distributor cam 58, which would otherwise tend to occur in the absence of the constraint means 60, with the consequent likelihood of causing misalignment of the electrical contact member 54 relative to the other electrical contact member 56 and also with the consequent likelihood of causing structural failure of the thin wall 20 of the envelope means 20. This is extremely important since rapid rotation of the distributor cam 58 in either direction would cause a high rate of extension and shortening of the thin-walled envelope 20, which would be very likely to cause early fatigue of the metal of which it is formed, with consequent likelihood of early rupture thereof and the consequent loss of the eifective sealed enclosure of the electrical contact means 54 and 56.

In the exemplary first form of the invention illustrated, the effective coupling of the above-mentioned longitudinal constraint means 60 between the rigid mounting bracket 24 and the cam-follower-mounting portion 62 of the envelope means 20 is accomplished by direct rigid connection of a rear end 65 of said longitudinal constraint means 60 to the rigid mounting bracket 24 by being clamped within the previously-mentioned clamp means 36 and by connection of an outward or front end 66 of said longitudinal constraint means 60 to the previously-mentioned cam follower means generally designated at 64, which, in turn, is effectively coupled to said cam-follower-mounting portion 62 of the envelope means 60 by the provision of a wire loop 68 rotatably carrying an outer cam-contacting roller 70 and with inner aligned inner ends 72 of said wire loop 68 being rotatably mounted in upper and lower apertured bosses 74 fixed to corresponding top and bottom side wall parts of the previously-mentioned cam follower mounting portion 62 of the envelope means 60.

It will be noted that, in the exemplary first form of the invention illustrated, the forward end 66 of the longitudinal constraint means 60 is actually integrally connected with respect to a bracket member 76 which is pivotally mounted on the outer portion of the wire loop 68 immediately above and below the roller means 70. This provides positive longitudinal constraint between the clamp 36 and the cam-follower-mounting portion 62 of the envelope means 20 and prevents any substantial elongation or shortening of the envelope means 20 therebetween in response to rotation of the cam 58, but freely allows lateral arcuate deflection of the envelope means 20 in the manner shown in two different sequential positions in FIGS. 1 and 2.

In the exemplary first form of the invention illustrated, the above-mentioned longitudinal constraint means 60 comprises effective biasing spring means normally forcibly resiliently cooperating with said cam-follower-mounting portion 62 of the envelope means 20 for forcibly resiliently laterally arcuately deflecting the envelope means 20 in a counter-clockwise direction as viewed in FIGS. 1 and 2 whereby to force the first contact member 54 carried therewith into electrical engagement with the second electrical contact member 56 carried by the inner rigid longitudinal support member 44. In said exemplary first form of the invention, the rear end of said constraint means, taking the form of the biasing spring means 60, is rigidly carried and mounted by the previously mentioned clamping means 36 of the mounting bracket means 24 and normally forcibly cooperates with the camfollower-mounting portion 62 of the envelope means 20 in a manner resiliently forcing same toward the left so as to relatively move said front portion 38 of the enclosing envelope means 20 with respect to the fixed contact member 56 whereby to bring about the normally closed relationship and electrical engagement of said first and second electrical contact means 54 and 56. However, when the conventional distributor cam 58 is rotated during operation of an associated internal combustion engine (not shown), the multiple points or lobes thereof, as indicated at 78, will forcibly ride against the cam follower means 64, which Will forcibly deflect the complete front end 38 of the cantilever enclosing envelope means 28 toward the right or in a clockwise direction around an effective pivot point which may be said to be located substantially at the point indicated by the reference numeral 80 in FIGS. 1 and 2 in a manner such as to relatively move the first electrical contact member 54 away from the fixed position second electrical contact member 56 into the open relationship shown in FIG. 2. This action will occur repetitively and very rapidly during the operation of an internal combustion engine, and between each such opening of. the first and second electrical contact members 54 and 56, they will automatically close under the resilient biasing action of the return biasing spring means 60.

Incidentally, it should be noted that the effective pivot or hinge point indicated at 80 is effectively caused by the provision of the silient flexible convolutions 82 (which may comprise one or more convolutions as desired or needed) which increase the compliance or reduce the stiffness of the complete longitudinal cantilever type enclosing envelope means 20 so as to effectively produce what might be called resilient flexible convoluted hinge or pivot means effectively operable about the pivot point 80.

In the exemplary first form of said cam follower means 64, the'roller means 70 thereof may be of hard wearresistant, electrically conductive, metallic material since 1t is in electrical contact with the enclosing envelope means 20 which is grounded and, therefore, it need not be made of an electrical insulating material, which is frequently not as wear-resisting, as is the case with conventional prior art distributor point assemblies.

An extremely important feature of the present invention is the fact that the hollow interior chamber 50 defined within the longitudinal cantilever-type enclosing envelope means 20 is provided with a substantially nonoxidizing or inert gaseous atmosphere therein which, therefore, completely covers and surrounds said first and second electrical contact members 54 and 56 and completely prevents oxidation thereof and also contamination thereof by exterior foreign matter, such as oil, grease, or

the like-this being the feature of the present invention which brings about the extended life of the electrical contact means comprising, in the example illustrated, said first and second electrical contact members 54 and 56.

It will be noted that the apparatus of the present invention provides a very convenient arrangement for placing the above-mentioned non-oxidizing inert gaseous atmosphere in the hollow interior of the enclosing envelope means 20, as indicated at 50, since the rigid longitudinal support member 44 comprises a hollow tube having an open forward end 84 and adapted to have its previously-mentioned rear end 46 initially open to provide a convenient means for evacuating the interior 50 of the enclosing envelope means 20 and then introducing a non-oxidizing or inert gas thereinto, after which said opening in said rear end 46 is effectively closed or provided with a closure seal.

It should be noted that the non-oxidizing or inert gaseous atmosphere referred to above may comprise any of the so-called inert gases such as argon, krypton, neon, xenon, or various other non-oxidizing gases, or, in certain cases, may merely comprise ordinary air at greatly reduced pressure-in other words, a substantial vacuum.

FIGS. 4 and 5 illustrate a very slight modification of the cam follower means and the front end of the longitudinal constraint means, and parts similar to those of the first form of the invention are designated by similar reference numerals, followed by the letter a, however. In this modification, it will be noted that the forward end of the longitudinal constraint means 60a is formed into an integral hook or eye 70a which comprises the cam-contacting surface and encircles the forward portion of the loop member 68a, which has its ends 72a mounted in the upper and lower bosses 74a in a manner similar to the corresponding structure of the cam follower means 64 of the first form of the invention. In other words, the major difference of this modification is the fact that the integral eye or hook portion 70a does not rotate with respect to the contacted surface of the cam 58a, but merely makes sliding contact therewith end, therefore, is normally made of some relatively hard wear-resistant material which may be either electrically conductive or non-conductive.

FIGS. 6 and 7 illustrate a further modification of the invention wherein similar parts are designated by similar reference numerals, followed by the letter b, however. This modification primarily relates to a modified cam follower means 64b wherein the forward end 66b of the constraint means 60b has an outward ridge 70b integrally formed therein, thus comprising a non-rotatable sliding type of cam-contacting surface, and wherein an extreme forward end 86 of the constraint means 60b is slidably mounted within a retaining hook means 88 fastened to the cam-follower-mounting portion 62b of the envelope means 20b. Otherwise, this modification of the invention is functionally quite similar to both the modification of FIGS. 4 and 5 and the first form of the invention illustrated in FIGS. l3.

FIGS. 8 and 9 illustrate a further modification of the invention, and parts similar to those of earlier forms of the invention are designated by similar reference numerals, followed by the letter 0, however. It will be noted that this modification is almost identical to the FIGS. 4 and 5 modification of the invention, but has a different means for attaching or coupling the cam follower means 640 to the cam-follower-m-ounting portion 62c of the envelope means 200, which, in this case, comprises an encircling ring 680, which is adapted to firmly grasp the exterior of the envelope 20c. Indeed, in certain forms of the invention, it may be soldered, welded, or otherwise positively fixed thereto. A wear-resistant spacer block 90 is optionally mounted between the integral hook or eye 700, comprising the cam follower means 64c, and this is useful when the fastening ring 680 is merely clamped around the exterior of the envelope means 200 and is unnecessary when said fastening ring 680 is positively fixed thereto by welding, soldering, or the like.

FIGS. 10 and 11 illustrate a further slight modification of the invention which actually comprises a very slight variation of the FIGS. 6 and 7 modification of the invention, and similar parts are designated by similar reference numerals, followed by the letter d, however. It will be noted that in this variation the extreme forward end 86d of the constraint means indicated generally at 60d is no longer engaged in a hook member such as that shown at 88- in FIGS. 6 and 7, but instead is mounted in a corresponding slot between a mounting ring 68d and a wear-resistant spacer block 90d. This provides a slightly different structure from that shown in FIGS. 6 and 7, but one which functions substantially the same, and it should be noted that the fastening band 68d may merely be clamped in the relationship shown or may be welded, soldered, or otherwise permanently affixed to the exterior of the envelope means 20d.

FIG. 12 is a fragmentary view similar to the remote end portion of the envelope means shown in the FIG. 1 form of the invention, and adjacent portions of the apparatus, but merely illustrates a reversed arrangement of the electrical contact means 54a and 56e such that they are normally open or disengaged when the cam follower means 64e lies against the flat 92 of the cam 58a in a position similar to that shown in the first form of the invention in FIG. 1. This effective operational reversal of the FIG. 12 modification of the invention is provided by reversing the positions of the contacts 54a and 566 relative to the corresponding contacts 54 and 56 of the first form of the invention shown in FIGS. 1-3. All parts of this modification which correspond to similar parts of the first form of the invention are designated by similar reference numerals, followed by the letter 6, however.

It should be noted that it is. not necessary that the longitudinal constraint means, such as that shown at 60 in the first form of the invention, for example, also comprises a biasing spring means, as illustrated and described in connection with the first form of the invention. Actually, two separate structures may be employed, one of them comprising a longitudinal constraint means having the required lateral compliance and a second structure comprising merely a lateral-action biasing spring means but not providing any substantial measure of longitudinal constraint means. Also, it should be noted that it is not necessary in all cases that the coupling of longitudinal constraint means, such as the exemplary one shown at 60 in the first form of the invention, to the envelope means, such as that shown at 20 in the first form of the invention, be provided by effective connection through the cam follower means, such as the exemplary structure shown at 64 in the first form of the invention. It is possible to divorce these two structures and to directly couple the front end of the longitudinal constraint means to the'envelope means independent of the cam follower means and to also couple the cam follower means to the envelope means in a manner completely independent of the front end of the longitudinal constraint means.

It should be understood that the figures and the specific description thereof set forth in this application are for the purpose of illustrating the present invention and are not to be construed as limiting the present invention to the precise and detailed specific structure shown in the figures and specifically described hereinbefore. Rather, the real invention is intended to include substantially equivalent constructions embodying the basic teachings and inventive concept of the present invention.

Iclaim:

1. Extended-life electrical contact means, comprising: hollow longitudinal cantilever enclosing envelope means of resilient electrically conductive material provided at a rear end thereof with rigid electrically conductive mounting bracket means flexibly mounting said cantilever envelope means in a cantilever manner extending outwardly therefrom, said envelope means having a sealed front end longitudinally spaced from said rear end and capable of being resiliently arcuately forcibly displaced from an initial rest position; a rigid longitudinal support member of electrically conductive material extending through the rear end of said envelope means and along the length thereof to an interior position in a predetermined interior relationship with respect to said front end of said envelope means and spaced from and out of contact with inside surfaces of said envelope means; a first electrical contact member effectively carried by an inside surface of a side portion of said envelope means and in electrical engagement therewith; and a second electrical contact member aligned with, opposed to, and facing said first electrical contact member and effectively carried by said rigid longitudinal support member within said envelope means and in electrical engagement with respect to said rigid longitudinal support member, said first and second electrical contact members together comprising an effective electrical switch; said rear end of said envelope means being provided with inner sealing plug means effectively closing and sealing same and being made of electrical insulating material effectively electrically insulating said rigid longitudinal support member from the rear end of said cantilever envelope means, an exterior side wall portion of said envelope means being provided with laterally directed cam follower means adapted for cam following engagement with a cam for corresponding cantilever deflection of said envelope means with respect to the non-deflected inner rigid longitudinal support member whereby to forcibly cause corresponding relative movement of said first and second electrical contact members within said sealed envelope means in an effective switch operating manner, said envelope means defining a completely sealed interior chamber provided with a substantially non-oxidizing gaseous medium therein; and longitudinal deflection-minimizing constraint means effectively longitudinally coupled between said rigid mounting bracket means and said camfollower-mounting side wall portion of said envelope means for substantially preventing longitudinal deflection of said envelope means therebetween and having lateral compliance sufficient to allow said corresponding cantilever deflection of said envelope means by said cam follower means in response to cam operation thereof.

2. Apparatus as defined in claim 1, wherein said effective coupling of said longitudinal deflection-minimizing constraint means between said rigid mounting bracket means and said side wall portion of said envelope means is provided by direct rigid connection of a rear end of said constraint means to said rigid mounting bracket means and connection of an outer front end of said constraint means to said cam follower means, which effectively couples said outer front end of said constraint means to said side wall portion of said envelope means. 7

3. Apparatus as defined in claim 2, wherein the relative positionings of said rigid longitudinal support member and said envelope means are such as to normally maintain said first and second electrical contact members in resilient electrical engagement.

4. Apparatus as defined in claim 2, wherein said rigid longitudinal support member has a rear end extending outside of the rear end of said cantilever envelope means and provided with electrical connector means for connection to a suitable source of electric power.

5. Apparatus as defined in claim 2, wherein said mounting bracket means is in electrical engagement with said rear end of said envelope means, said rigid longitudinal support member having a rear end extending outside of the rear end of said cantilever envelope means and provided with electrical connector means for connection to a suitable source of electric power.

6. Apparatus as defined in claim 2, wherein said rigid longitudinal support member comprises a hollow tube having an opening positioned within said envelope means and having an initially open rear end for providing said interior chamber within said envelope means with said substantially non-oxidizing gaseous medium and then being provided with a closure seal for subsequently maintaining same.

7. Apparatus as defined in claim 2, wherein said cantilever envelope means is inherently provided with an effective pivot point adjacent to said rear end and positioned outwardly of the mounting engagement thereof with respect to said mounting bracket means, each of said first and second electrical contact members being spaced from said effective pivot point by a distance substantially equivalent to the corresponding radius of pivotal rotation of the resilently movable one of said electrical contact members.

8. Apparatus as defined in claim 2, wherein said longitudinal deflection-minimizing constraint means comprises effective biasing spring means normally forcibly resiliently cooperating with said cam-follower-mounting side wall portion of said envelope means for forcibly resiliently laterally arcuately deflecting said cantilever envelope means in a manner such as to force said first interiorly mounted electrical contact member carried therewithin into electrical engagement with said second electrical contact member carried by said inner rigid longitudinal support member.

9. Apparatus as defined in claim 2, wherein the front end of said cantilever envelope means is of initially open tubular construction provided with a sealing closure cap positioned thereover after interior adjustment of said first and second electrical contact members for aligned engaging and disengaging relative movement thereof.

10. Apparatus as defined in claim 2, wherein said cam follower means comprises a rotatably mounted frictionminimizing roller means mounted for rotation in response to forcible rotary abutment therewith of said cam.

11. Apparatus as defined in claim 2, wherein said cam follower means comprises a projection having a wear resistant contact surface adapted for sliding cam following abutment with respect to said cam during forcible contact therewith.

12. Apparatus as defined in claim 2, wherein said mounting bracket means is of a size and shape such, and is provided with attachment means positioned such, as to be adapted for direct attachment to the pro-existing engagement portions of a conventional internal combustion engine distributor, with said cam follower means positioned at the proper location for engagement with and operation by said cam, which takes the form of a conventional multi-lobed internal combustion engine distributor cam.

13. Apparatus as defined in claim 2, wherein said cantilever envelope means is provided with effective resilient flexible convoluted hinge means adjacent to said rear end and positioned outwardly of the mounting engagement thereof with respect to said mounting bracket member and providing an effective pivot point, each of said first and second electrical contact members being spaced from said effective pivot point by a distance substantially equivalent to the corresponding radius of pivotal rotation of the resiliently movable one of said electrical contact members.

14. Apparatus as defined in claim 2, wherein the relative positionings of said rigid longitudinal support member and said envelope means are such as to normally maintain said first and second electrical contact members in electrically disengaged relationship.

15. Apparatus as defined in claim 2, wherein said cam follower means comprises an effectively electrically grounded rotatably mounted friction-minimizing roller means mounted for rotation in response to forcible rotary abutment therewith of said cam.

16. Apparatus as defined in claim 2, wherein said cam follower means comprises I an effectively electrically grounded projection having a Wear resistant contact surface adapted for sliding cam following abutment with respect to said cam during forcible contact therewith.

17. Apparatus as defined in claim 2, wherein said longitudinal deflection-minimizing constraint means comprises effective biasing spring means normally forcibly resiliently cooperating with said cam-follower-mounting side wall portion of said envelope means for forcibly resiliently laterally arcuately deflecting said cantilever envelope means in a manner such as to force said first interiorly mounted electrical contact member carried therewithin said second electrical contact member carried by said inner rigid longitudinal support member.

References Cited UNITED STATES PATENTS ROBERT K. SCHAEFER, Primary Examiner.

into electrically disengaged relationship with respect to 10 JONES, Assistant Examine)- 

1. EXTENDED-LIFE ELECTRICAL CONTACT MEANS, COMPRISING: HOLLOW LONGITUDINAL CANTILEVER ENCLOSING ENVELOPE MEANS OF RESILIENT ELECTRICALLY CONDUCTIVE MEATEIAL PROVIDED AT A REAR END THEREOF WITH RIGID ELECTRICALLY CONDUCTIVE MOUNTING BRACKET MEANS FLEXIBLY MOUNTING SAID CANTILEVER ENVELOPE MEANS IN A CANTILEVER MANNER EXTENDING OUTWARDLY THEREFROM, SAID ENVELOPE MEANS HAVING A SEALED FRONT END LONGITUDINALLY SPACED FROM SAID REAR END AND CAPABLE OF BEING RESILIENTLY ARCUATELY FORCIBLY DISPLACED FROM AN INITIAL REST POSITION; A RIGID LONGITUDINAL SUPPORT MEMBER OF ELECTRICALLY CONDUCTIVE MATERIAL EXTENDING THROUGH THE REAR END OF SAID ENVELOPE MEANS AND ALONG THE LENGTH THEREOF TO AN INTERIOR POSITION IN A PREDETERMINED INTERIOR RELATIONSHIP WITH RESPECT TO SAID FRONT END OF SAID ENVELOPE MEANS AND SPACED FROM AND OUT OF CONTACT WITH INSIDE SURFACES OF SAID ENVELOPE MEANS; A FIRST ELECTRICAL CONTACT MEMBER EFFECTIVELY CARRIED BY AN INSIDE SURFACE OF A SIDE PORTION OF SAID ENVELOPE MEANS AND IN ELECTRICAL ENGAGEMENT THEREWITH; AND A SECOND ELECTRICAL CONTACT MEMBER ALIGNED WITH, OPPOSED TO, AND FACING SAID FIRST ELECTRICAL CONTACT MWMBER AND EFFECTIVELY CARRIED BY SAID RIGID LONGITUDINAL SUPPORT MEMBER WITHIN SAID ENVELOPE MEANS AND IN ELECTRICAL ENGAGEMENT WITH RESPECT TO SAID RIGID LONGITUDINAL SUPPORT MEMBER, SAID FIRST AND SECOND ELECTRICAL CONTACT MEMBERS TOGETHER COMPRISING AN EFFECTIVE ELECTRICAL SWITCH; SAID REAR END OF SAID ENVELOPE MEANS BEING PROVIDED WITH INNER SEALING PLUG MEANS EFFECTIVELY CLOSING AND SEALING SAME AND BEING MADE OF ELECTRICAL INSULATING MATERIAL EFFECTIVELY ELECTRICALLY INSULATING SAID RIGID LONGITUDINAL SUPPORT MEMBER FROM THE REAR END OF SAID CANTILEVER ENVELOPE MEANS, AN EXTERIOR SIDE WALL PORTION OF SAID ENVELOPE MEANS BEING PROVIDED WITH LATERALLY DIRECTED CAM FOLLOWER MEANS ADAPTED FOR CAM FOLLOWING ENGAGEMENT WITH A CAM FOR CORRESPONDING CANTILEVER DEFLECTION OF SAID ENVELOPE MEANS WITH RESPECT TO THE NON-DEFLECTED INNER RIGID LONGITUDINAL SUPPORT MEMBER WHEREBY TO FORCIBLY CAUSE CORRESPONDING RELATIVE MOVEMENT OF SAID FIRST AND SECOND ELECTRICAL CONTACT MEMBERS WITHIN SAID SEALED ENVELOPE MEANS IN AN EFFECTIVE SWITCH OPERATING MANNER, SAID ENVELOPE MEANS DEFINING A COMPLETELY SEALED INTERIOR CHAMBER PROVIDED WITH A SUBSTANTIALLY NON-OXIDIZING GASEOUS MEDIUM THEREIN; AND LONGITUDINAL DEFLECTION-MINIMIZING CONSTRAINT MEANS EFFECTIVELY LONGITUDINALLY COUPLED BETWEEN SAID RIGID MOUNTING BRACKET MEANS AND SAID CAMFOLLOWER-MOUNTING SIDE WALL PORTION OF SAID ENVELOPE MEANS FOR SUBSTANTIALLY PREVENTING LONGITUDINAL DEFLECTION OF SAID ENVELOPE MEANS THEREBETWEEN AND HAVING LATERAL COMPLIANCE SUFFICIENT TO ALLOW SAID CORRESPONDING CANTILEVER DEFLECTION OF SAID ENVELOPE MEANS BY SAID CAM FOLLOWER MEANS IN RESPONSE TO CAM OPERATION THEREOF. 